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authorMing Lei <ming.lei@redhat.com>2018-12-18 12:15:29 +0800
committerJens Axboe <axboe@kernel.dk>2018-12-17 21:35:07 -0700
commitcd19181bf9ad4b7f40f2a4e0355d052109c76529 (patch)
tree30896b4375d72ec6097eedfebaf193b368d9db0e /block
parent3c94d83cb352627f221d971b05f163c17527de74 (diff)
downloadlinux-0-day-cd19181bf9ad4b7f40f2a4e0355d052109c76529.tar.gz
linux-0-day-cd19181bf9ad4b7f40f2a4e0355d052109c76529.tar.xz
blk-mq: enable IO poll if .nr_queues of type poll > 0
The queue mapping of type poll only exists when set->map[HCTX_TYPE_POLL].nr_queues is bigger than zero, so enhance the constraint by checking .nr_queues of type poll before enabling IO poll. Otherwise IO race & timeout can be observed when running block/007. Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
-rw-r--r--block/blk-mq.c3
-rw-r--r--block/blk-sysfs.c3
2 files changed, 4 insertions, 2 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c
index b0888a89fa662..2de9728574963 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2833,7 +2833,8 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
q->tag_set = set;
q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT;
- if (set->nr_maps > HCTX_TYPE_POLL)
+ if (set->nr_maps > HCTX_TYPE_POLL &&
+ set->map[HCTX_TYPE_POLL].nr_queues)
blk_queue_flag_set(QUEUE_FLAG_POLL, q);
if (!(set->flags & BLK_MQ_F_SG_MERGE))
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index bb7c642ffefa5..0619c8922893a 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -402,7 +402,8 @@ static ssize_t queue_poll_store(struct request_queue *q, const char *page,
unsigned long poll_on;
ssize_t ret;
- if (!q->tag_set || q->tag_set->nr_maps <= HCTX_TYPE_POLL)
+ if (!q->tag_set || q->tag_set->nr_maps <= HCTX_TYPE_POLL ||
+ !q->tag_set->map[HCTX_TYPE_POLL].nr_queues)
return -EINVAL;
ret = queue_var_store(&poll_on, page, count);